Because the ports used for data transfer between the RS-FEC engine and the SerDes are identical to those used by the Integrated 100G Ethernet, and the bypass control of the RS-FEC layer is performed within the 100G Ethernet integrated block, the inclusion of the RS-FEC functionality within the Ethernet subsystem is mostly transparent to the user in normal mode.
To enable the RS-FEC in normal mode, set the
ctl_rx_rsfec_enable and ctl_tx_rsfec_enable
inputs to 1, and set ctl_rsfec_enable_transcoder_bypass_mode to 0.
Set the desired operating sub-mode on the
ctl_rsfec_ieee_error_indication_mode,
ctl_rx_rsfec_enable_correction and
ctl_rx_rsfec_enable_indication inputs. The
rx_reset and tx_reset must then be asserted
and removed in order to apply the chosen settings.
In normal mode, all of the statistics outputs defined in Common Ports are generated regardless of the chosen sub-mode.
The codeword statistics flags (stat_rx_rsfec*_cw_inc) output from the RS-FEC engine in normal
mode should be interpreted as per the following table.The RS-FEC engine never generates the values in rows marked as "illegal".
| cw_inc | corrected_cw_inc | uncorrected_cw_inc | Description |
|---|---|---|---|
| 0 | 0 | 0 | No activity |
| 0 | 0 | 1 | Illegal |
| 0 | 1 | 0 | Illegal |
| 0 | 1 | 1 | Illegal |
| 1 | 0 | 0 | Codeword had no errors |
| 1 | 0 | 1 | Codeword had errors that were not corrected |
| 1 | 1 | 0 | Codeword had errors that were corrected |
| 1 | 1 | 1 | Illegal |